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Carnegie Mellon Goes to the Super Bowl
Football fans tuning into this years Super
Bowl were treated to a unique new view of the action during
playbacks. CBS Television used
a new technology co-developed by the network and Carnegie Mellon
computer vision expert Takeo Kanade.
Eye Vision, as CBS calls it, involves shooting multiple
video 01_images of a dynamic event, such as a football game, from
multiple cameras placed at different angles. The video streams from
these cameras are combined by computer and the resulting 01_images
reach viewers in a format that will make them feel as if they are
flying through the scenes they see.
The action at Super Bowl XXXV was captured by more than 30 cameras,
each poised some 80 feet above the field at Raymond
James Stadium in Tampa, Fla. Each camera, with computer-controlled
zoom and focus capabilities, was mounted on a custom-built, robotic
pan-tilt head, which could swing the camera in any direction at
the command of a computer. These camera heads were controlled in
concert so that cameras pointed, zoomed and focused at the same
time on the same spot on the field, where a touch down or fumble
occurred.
How does the system work? One of the camera heads is designated
as the master camera. A human camera operator manipulates a movable
pan-tilt tripod attached to a TV screen on which the video from
the master camera is constantly displayed. The pan-tilt tripod is
equipped with sensors to constantly measure its angle. The master
camera head moves by mimicking the motion of the tripod as the camera
operator moves it to capture a moving object on the field on his
or her TV screen.
In the meantime, information collected from the master cameras
pan-tilt angles, zoom and focus is fed to a computer, which quickly
computes the appropriate control signal for each of the remaining
cameras. This causes all of them to converge on the same target
and capture its image from a variety of angles.
Live action on the football field is continuously captured up
to 30 times per second by the video cameras. The video of each camera
is synchronized and time stamped so that all the views at the most
critical and interesting moments can be played back in sequence,
as if a viewer had flown around the action.
Kanade explained his technology in an interview from Tampa, which
aired during the Super Bowl Pre-Game Show. He noted that the Eye
Vision demonstration that will appear on Super Bowl Sunday
is only a small part of this new technology, which he calls Virtualized
Reality as opposed to virtual reality. It is the product
of more than six years of research.
For this modeling technology to achieve its full impact, the set
of captured, multiple video 01_images must be processed beyond the
play back. The detailed geometrical information about a scene is
extracted by computer, which enables a person to choose how to view
a scene, even from a perspective that was not shot by any camera.
To bring this concept to life, Kanade and his students built a
3D room equipped with more than 50 video cameras, and
experimented by filming people involved in a variety of sports activities.
He also spun off a company named Zaxel
Systems, Inc., for commercialization of the technology. Much
of this work can be viewed at the Virtualized
Reality Web site.
In contrast to virtual reality, in which synthetic environments
are created, Virtualized Reality technology, and to a lesser
extent, Eye Vision, are based on events taking place in the real
world, which are captured and processed by computer manipulation.
Because our models are derived from real 01_images,
Kanade says, the models look much more real than typical virtual
worlds.
Kanade says the output from these multiple cameras shooting a
scene together from many angles actually can create totally new
views that were not captured by any camera. As this technology develops,
he believes it will create a completely new way to view sports and
entertainment events. People will be able to customize the perspective
from which they watch, for example, from that of a particular player
or the ball.
Kanade is the former director of Carnegie Mellons Robotics
Institute. He has been a leader in the development of video-based
vision systems used in the universitys autonomous vehicles
and exploration robots. His team has developed a vision-based autonomous
helicopter, which ultimately may be able to aid in search and rescue
operations, fire fighting and inspection tasks.
He is also a pioneer in medical robotics and computer-assisted
surgery, working with surgeons and medical professionals to develop
smart tools capable of performing medical procedures better than
a physician or machine could do alone.
Kanade earned his undergraduate and graduate degrees in electrical
engineering from Kyoto
University, Japan. He has been on the Carnegie Mellon faculty
since 1980 and director of the Robotics Institute since 1991. He
is a member of the National
Academy of Engineering. Most recently he received a $100,000
award from the NEC Foundation for C&C Promotion for fundamental
and broad contributions to the development of multimedia through
the advancement of robotics and computer vision.
Reprinted with kind permission from Lisa Kulick,
Carnegie Mellon associate director of public relations - Web development
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